As the person on the receiving end of such missives, I can tell you that, best case scenario, they are received with extreme patience and an eye roll. I think sharing this type of material every once in a while is okay, but your kids would probably rather get a quick message that says "Hi, I love you, how are you doing?" than yet another thinly veiled mom-knows-best lecture. I think it would probably suit your goal better as well, which I'm guessing is actually to find a way to maintain contact with your family now that they've grown.